08-11-2017 05:31 PM
RE: U2711b, yellow spot
Don't know what you mean by "matrix". I think you mean the panel itself. Dell does not repair monitors, sell monitor components, or have disassembly documentation. Your only option is to look for spare parts on eBay or craigslist.
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Run the PC pre-Windows diagnostics
Run the Monitor Reset & BID (Built-in Diagnostics)
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